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Topic C1- Atomic structure and the periodic table - Coggle Diagram
Topic C1- Atomic structure and the periodic table
Atoms
the nucleus
It is in the middle of an atom
it contains protons and neutrons
the nucleus has a radius of around 1x10^-14
it has a positive charge because of its protons
almost the whole mass of the atom is concentrated in the nucleus
electrons
move around the nucleus in electron shells
they're negatively charged and tiny, but they cover a lot of space
the volume of their orbits determines the size of the atom.
electrons have virtually no mass
number of protons equals number of electrons
this is because they have the same number of protons as electrons
the charge on the electrons is the same size as the charge on the protons. but opposite - so the charges cancel out
atoms are neutral- they have no charge overall (unlike ions)
in an ion, the number of protons doesn't equal the number of electrons. this means it has an overall charge. For example an ion with a 2- charge, has two more electrons than protons.
atomic number and mass number describe an atom
the nuclear symbol of an atom tells you its atomic number and mass number
the atomic number tells you how many protons there are
the mass number tells you the total number of protons and neutrons in the atom
to get the number of neutrons, just subtract the atomic number from the mass number
Elements